The present invention relates to an integrated network QoS (Quality of Service (referred to as “QoS”)) control system that manages and controls a bandwidth and the QoS in an integrated network. In the integrated network, data is transmitted between a bandwidth-guaranteed network and a bandwidth-not-guaranteed network (or a bandwidth-guaranteed network and a bandwidth-not-guaranteed network are inter-linked and communications can be conducted between a terminal on the bandwidth-guaranteed network and a terminal on the bandwidth-not-guaranteed network inter-linked).